1. Technical Field
This disclosure relates generally to integrated circuit layouts and design, and more particularly to voltage source controllers, devices, and methods for controlling voltage of memory cells.
2. Description of the Related Art
In recent years, mobile devices such as smart phones and tablet computers have become increasingly sophisticated. In addition to supporting telephone calls, many mobile devices now provide access to the internet, email, text messaging, and navigation using the global positioning system (GPS). Mobile devices that support such sophisticated functionality often include many components. To remain mobile, physical size of such components of a mobile device is a design concern. Further, many mobile devices operate on battery power. Reducing power consumption of components of a mobile device, therefore, is also a design concern.
Computer memory technologies have improved in reducing power consumption. Memory arrays, for example, are often operated in various low-power modes, such as a retention mode and a write assist mode. In the retention mode, core operating power of memory cells of the memory array may be reduced to a minimum voltage that enables the data stored within the cell to remain. Lowering the voltage below such a minimum voltage may cause the data to be lost. In the write assist mode, voltage to a memory cell may be reduced such that writing a bit to a memory cell requires less power.
In memory arrays of the prior art, separate hardware is utilized to effect the retention mode and the write assist mode. That is, one set of hardware is utilized to effect the retention mode while another, different set of hardware is utilized to effect the write assist mode. Each set of hardware correspondingly requires its own area on a chip or in a device.